He seemed to favour a palette of warm colours (orange, red, violet) with accents of cooler blues and greens, though of course with Warhol there were no rules.

Now, look at this striking portrait of Helena Rubenstein, by René Bouché. It was one of many portraits in the (superb) current show devoted to the grande dame, at New York's Jewish Museum.

Portrait of Helena Rubenstein,
by René Bouché

When analyzing a painting's colour scheme, it's important to note not only the proportion of each colour, but also the blacks and whites that we don't really notice at first.

With a deep blanket of snow on the ground, I have been spending time in my studio, dyeing cotton in the hot colours inspired by these works.

I have been using a new guide to dyeing published by Diane Franklin, Dyeing Alchemy: A Primer about Procion MX Dyeing. It consists of a manual with almost 100 pages of general information, and a downloadable, interactive spreadsheet. Basic to her approach is the weighing of fabric and dye, and having on hand pre-mixed quantities of urea solution, dye solution, salt solution and soda ash solution. Before beginning, I had to go to a kitchen supply store to pick up an electronic scale.

The spreadsheet allows the user to enter the weight of the cotton to be dyed and the intensity of the desired colour, and then gives precise quantities of the various stocks to be used. Though Franklin purports to "take out the math" for the hand dyer, her method is less casual than the usual "one tablespoon of this, two cups of that" approach. Quantities are more likely to be down to the single gram and millilitre, 367 ml, for example. The result is less serendipitous, with less waste.

My results so far have been strong and vibrant, with more subtle mottling than with other methods. This may have something to do with the relatively large quantities of salt Franklin recommends, and the urea required for the dye stock. Or maybe it's that I have been using pure pigments rather than blends. I'm not using any more agitation or liquid than I have with past methods.

Shown here is a range of tangerine to fuchsia to "mixing red". Keep in mind that it is sometimes difficult to capture reds in a photo.

I am looking forward to using some of these gorgeous colours in my new work. I'm also enjoying the dyeing so much that I might just see what else I can add to my working palette before putting away the dye pots.